应用

应用注释

Portable XRF Screening for the Presence of Cobalt Dust

Fast, Cost-Effective, On-Site Method for Testing Reactor Bound Components

Focus
Portable XRF
Handheld XRF
Non-Destructive Testing
On-Site Smear/Wipe Testing
Cobalt Dust Verification

The Problem

If Cobalt dust makes its way into a nuclear plant reactor, the reactor enriches stable Cobalt 59 creating the highly radioactive Cobalt-60 isotope. Cobalt-60 has a half life just over 5 years and it emits emits beta particles and gamma radiation at energies of 1.17 MeV and 1.33 MeV. Cobalt-60 is a health hazard and a disposal problem.

When cobalt dust contaminated components are installed in a reactor, the issue of having to manage unwanted Cobalt- 60 results. To avoid this problem, every effort is made to keep cobalt dust out of the nuclear reactor.

A Common Cobalt Management Solution

Current industry practice is to inspect reactor bound components. "Surface wipe" or "smear samples" are taken on alloy components such as tubing, valves, and piping. Inner and outer surfaces edges are wiped. Valves may be disassembled so inner surfaces can be accessed and sampled. The smear/wipe samples are sent to a laboratory for analysis, however, laboratory analysis can be both expensive and slow.

Portable XRF is ideal for Cobalt Dust Screening at Nuclear Power Plants; Radiation Safety Professionals can screen thousands of samples on-site, with immediate results, rather than waiting for costly, time-consuming lab tests.

Immediate, Real-time Cobalt Management Solution Using Innov-X Portable XRF

With portable XRF systems, metals such as cobalt can be measured at levels in the low micro-gram per wipe range, on site and within minutes. With on-site smear/wipe testing, radiation safety professionals can know immediately whether a component is contaminated by cobalt dust. Beyond the speed and convenience for a single sample, more samples can be run at a much lower cost per sample. This reduces the risk of introducing cobalt dust into the reactor.

Background

Nuclear power plants use a process fluid system to move heat from the nuclear reactor to the steam turbine side of their energy generating process. These systems typically use stainless steels and high grade nickel alloy piping to move the liquid coolant. Alloy fabricators and producers that manufacture the piping and components may also make or handle alloys containing cobalt (Stellite Alloys, for example). Cobalt alloys are prone to producing a fine dust which can deposit on other material, such as the piping bound for nuclear reactors.

Olympus Innov-X offers two options to screen for Cobalt, and other heavy metals in your alloy components: Our signature handheld XRF and our revolutionary portable XRF...choose the one that is right for you:

Innov-X Analyzers Go Beyond Cobalt Wipes...
Cleanliness Testing:	Presence or absence of over 20 common alloying elements can be noted at receiving. This gives operating personnel valuable information about he cleanliness of reactor bound components, and which contaminants are common to which components
Material Verification:	Test alloy grades at receiving or installation to avoid mix-ups
In-Service Testing:	Wipe test on components in-service or coming out of service can provide useful information on over 80 elements
Radioactive Element Screening:	The presence of elements like Americium, Curium, Plutonium or Uranium can be discovered during a routine wipe test from an in-service area. While the particular isotope cannot be determined, the elements can be identified and relative amounts estimated

The DELTA is a battery powered handheld analyzer with a 4W, 40 kV x-ray tube. This analyzer can test wipe samples and small components utilizing a shielded test stand with safety interlocks. It can also be used for direct hand held testing of large alloy components in-situ at any location in the plant.

The X-5000 XRF is a self contained portable analyzer with a 10W, 50 kV tube which can run on ac or battery power. Simple to operate with the most powerful x-ray tube in a portable analyzer. This closed-beam system is the only safe way to do 50kV. The X-5000 has a safety interlocked lid so that x-rays are produced only when the lid is closed.